With the development of electronic technology, electronic terminals become increasingly widespread. Smart terminals such as mobile phones and tablet computers have become necessary terminal devices. Various applications can be installed in these terminal devices for providing users with various services.
Of course, conventional terminal devices are capable of storing data contents required by users. For example, when a user take or receive pictures, these pictures can be stored in an associated terminal. In order to take full advantage of the terminal device's own storage space, the terminal device will compress the pictures, typically in a JPEG format, and then store the compressed pictures. In this way, the storage requirement on the storage device of the terminal can be reduced.
However, the conventional picture compression scheme is limited and thus cannot reduce the data space occupied by pictures, resulting in large space occupation by the pictures.